limits maximum number of messages able to send per day

app/models/direct_message.rb

@@ -1,4 +1,22 @@
 class DirectMessage < ActiveRecord::Base
   belongs_to :sender,   class_name: 'User', foreign_key: 'sender_id'
   belongs_to :receiver, class_name: 'User', foreign_key: 'receiver_id'
+
+  validates :title,    presence: true
+  validates :body,     presence: true
+  validates :sender,   presence: true
+  validates :receiver, presence: true
+  validate  :max_per_day
+
+  scope :today, lambda { where('DATE(created_at) = ?', Date.today) }
+
+  def max_per_day
+    return if errors.any?
+    max = Setting[:direct_message_max_per_day]
+
+    if sender.direct_messages_sent.today.count >= max.to_i
+      errors.add(:title, I18n.t('activerecord.errors.models.direct_message.attributes.max_per_day.invalid', max: max))
+    end
+  end
+
 end

app/models/user.rb

@@ -23,7 +23,8 @@ class User < ActiveRecord::Base
   has_many :spending_proposals, foreign_key: :author_id
   has_many :failed_census_calls
   has_many :notifications
-  has_many :direct_messages
+  has_many :direct_messages_sent,     class_name: 'DirectMessage', foreign_key: :sender_id
+  has_many :direct_messages_received, class_name: 'DirectMessage', foreign_key: :receiver_id
   belongs_to :geozone
 
   validates :username, presence: true, if: :username_required?

config/locales/activerecord.en.yml

@@ -78,6 +78,10 @@ en:
           attributes:
             tag_list:
               less_than_or_equal_to: "tags must be less than or equal to %{count}"
+        direct_message:
+          attributes:
+            max_per_day:
+              invalid: "You can only send a maximum of %{max} direct messages per day"
         proposal:
           attributes:
             tag_list:

config/locales/activerecord.es.yml

@@ -78,6 +78,10 @@ es:
           attributes:
             tag_list:
               less_than_or_equal_to: "los temas deben ser menor o igual que %{count}"
+        direct_message:
+          attributes:
+            max_per_day:
+              invalid: "Sólo puedes enviar %{max} mensajes directos por día"
         proposal:
           attributes:
             tag_list:

db/seeds.rb

@@ -77,3 +77,4 @@ Setting['banner-img.banner-img-three'] = "Banner image 3"
 
 # Proposal notifications
 Setting['proposal_notification_minimum_interval_in_days '] = 3
+Setting['direct_message_max_per_day '] = 3

spec/features/direct_messages_spec.rb

@@ -72,4 +72,33 @@ feature 'Direct messages' do
     expect(page).to have_content error_message
   end
 
+  context "Limits" do
+
+    background do
+      Setting[:direct_message_max_per_day] = 3
+    end
+
+    scenario "Can only send a maximum number of direct messages per day" do
+      sender   = create(:user, :level_two)
+      receiver = create(:user, :level_two)
+
+      3.times { create(:direct_message, sender: sender) }
+
+      login_as(sender)
+      visit user_path(receiver)
+
+      click_link "Send private message"
+
+      expect(page).to have_content "Send private message to #{receiver.name}"
+
+      fill_in 'direct_message_title', with: "Hey!"
+      fill_in 'direct_message_body',  with: "How are you doing?"
+      click_button "Send message"
+
+      expect(page).to have_content "You can only send a maximum of 3 direct messages per day"
+      expect(page).to_not have_content "You message has been sent successfully."
+    end
+
+  end
+
 end

spec/models/direct_message_spec.rb

@@ -0,0 +1,85 @@
+require 'rails_helper'
+
+describe DirectMessage do
+
+  let(:direct_message) { build(:direct_message) }
+
+  before(:each) do
+    Setting[:direct_message_max_per_day] = 3
+  end
+
+  it "should be valid" do
+    expect(direct_message).to be_valid
+  end
+
+  it "should not be valid without a title" do
+    direct_message.title = nil
+    expect(direct_message).to_not be_valid
+  end
+
+  it "should not be valid without a body" do
+    direct_message.body = nil
+    expect(direct_message).to_not be_valid
+  end
+
+  it "should not be valid without an associated sender" do
+    direct_message.sender = nil
+    expect(direct_message).to_not be_valid
+  end
+
+  it "should not be valid without an associated receiver" do
+    direct_message.receiver = nil
+    expect(direct_message).to_not be_valid
+  end
+
+  describe "maximum number of direct messages per day" do
+
+    it "should not be valid if above maximum" do
+      sender = create(:user)
+      direct_message1 = create(:direct_message, sender: sender)
+      direct_message2 = create(:direct_message, sender: sender)
+      direct_message3 = create(:direct_message, sender: sender)
+
+      direct_message4 = build(:direct_message, sender: sender)
+      expect(direct_message4).to_not be_valid
+    end
+
+    it "should be valid if below maximum" do
+      sender = create(:user)
+      direct_message1 = create(:direct_message, sender: sender)
+      direct_message2 = create(:direct_message, sender: sender)
+
+      direct_message3 = build(:direct_message)
+      expect(direct_message).to be_valid
+    end
+
+    it "should be valid if no direct_messages sent" do
+      direct_message = build(:direct_message)
+
+      expect(direct_message).to be_valid
+    end
+
+  end
+
+  describe "scopes" do
+
+    describe "today" do
+      it "should return direct messages created today" do
+        direct_message1 = create(:direct_message, created_at: Time.zone.now.beginning_of_day + 3.hours)
+        direct_message2 = create(:direct_message, created_at: Time.zone.now)
+        direct_message3 = create(:direct_message, created_at: Time.zone.now.end_of_day)
+
+        expect(DirectMessage.today.count).to eq 3
+      end
+
+      it "should not return direct messages created another day" do
+        direct_message1 = create(:direct_message, created_at: 1.day.ago)
+        direct_message2 = create(:direct_message, created_at: 1.day.from_now)
+
+        expect(DirectMessage.today.count).to eq 0
+      end
+    end
+
+  end
+
+end